The modern toilet consists of three major parts, (1) an upper toilet water tank which functions as a water reservoir, (2) a lower part consisting of a bowl that also contains a volume of water into which is deposited human waste products and (3) a flushing apparatus. Once the waste products have been deposited, they are flushed away by activating the flushing apparatus which allows the water held in the upper tank section to flow into the bowl. The waste products are flushed into a collection system, such as a sewer system or septic tank, after which the water tank and bowl are refilled in preparation for a subsequent flush.
Waste products consist of solid and liquid waste. In presently available toilets, one flush is utilized to carry away both solid and liquid waste, even for occasions when there is only liquid waste in the bowl. In these toilets, a complete flush is effected with each flush and the total contents of the upper tank section is drained into the bowl and then out into the sewer system.
One of the most popular toilet flushing apparatuses uses a ball-cock valve assembly that controls the inlet of water into the toilet water tank. A float ball is connected to the ball-cock valve by means of a float arm. As the toilet tank fills with water, the buoyant float ball rises in the tank section, the motion being transmitted to the ball-cock through the float arm until at a predetermined water level the ball-cock assembly shuts off the water inlet to the tank. In most toilets, the water level in the water tank may be adjusted by means of a screw set mechanism provided in the ball-cock assembly. This adjustment, however, is limited in range and requires that the tank lid be lifted to obtain access to the ball-cock. Once the water level in the tank is set, the adjustment is usually thereafter ignored. The same volume of water is therefore discharged form the tank every time that the flushing apparatus is tripped, regardless of the volume which may be actually required on a particular occasion in order to successfully flush the toilet.
It is a well known fact that the largest use of water in most households and in many office buildings is for flushing toilets. Because the flushing is carried out with the full capacity of the water in the water tank the water usage is wasteful and not required. Considerable interest has been centered on reducing the water used when toilets are flushed, especially at times and in places when there is a water deficiency or periods of drought.
Several water saving methods are in current use to conserve water during the toilet flushing operation. One such method is to place a filled water bag or a solid object, such as a brick, in the water tank to displace an equivalent volume of water to thus reduce the volume of water consumed with each flushing. Another common method is to lower the float valve to allow the ball-cock valve to close at a reduced water level. These methods to conserve water in many cases are self-defeating, in that, the effectiveness of the partial flush is diminished, because it may be necessary to flush twice to effect a sanitary flush. Additionally, such methods represent a compromise in that once the volume of water is set, it is not readily adjustable.
In summary, the design of the prior art apparatuses with respect to the design of the instant invention are relatively complicated, require modification of the existing hardware and in some cases, the toilet tank itself requires modification.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention however, the following U.S. patents were considered related:
______________________________________ U.S. PAT. NO. INVENTOR ISSUED ______________________________________ 4,945,581 Harris 7 August 1990 4,937,894 Hill, et al 3 July 1990 4,910,812 Comparetti 27 March 1990 4,837,867 Miller 13 June 1989 ______________________________________
The Harris patent discloses a flush tank water saver that has an elongated semi-circular base that is clamped to the overflow tube. The base has an operating lever on pivots that is close to the flapper valve pivots. This lever engages the flapper valve at its center and pushes it in its direction of travel. The lever is operated to close the valve by means of a float mounted on the other side of the overflow tube. The float operates a float lever connected to the valve and a stop for the float is brought into place by the flush lever. When the flush handle is depressed for two seconds, the float engages the stop and is inoperative for that flush to thus, effect a full flush.
The Hill patent discloses a dual-flush toilet valve assembly that allows selection of either a partial or a complete flush of a toilet water tank. The invention features a hollow valve member having both a small vent bore and a larger opening. The valve is selectively pivoted in a first or a second direction depending upon which one of two activation levers is depressed. Opening the valve allows trapped air to vent from within the hollow valve. The inflowing water eventually imparts a negative buoyancy to the valve assembly allowing it to seat in the drain valve and seal the toilet tank prior to the complete discharge of the contained water. Alternatively, opening the valve allows less air to escape and therefore, the valve does not achieve a negative buoyancy. Therefore, the entire water contents of the toilet tank is allowed to drain before the valve is sealed onto the valve seat of the drain valve.
The Comparetti patent discloses a semi-flush valve mechanism in a toilet tank that is provided with a two way flush operating handle. If the handle is pressed downward, the toilet tank provides a complete flush in the conventional way. If the handle is pressed upwardly, the toilet tank provides a partial flush. A pivotally extended vane on a tilted valve assembly receives a water stream from a refill tube. This action restores the toilet tank valve assembly to its closed upright position to allow the partial flush.
The Miller patent discloses a toilet dual-flush system that allows a full flush or a partial flush to carry away liquid wastes. The system functions by partially opening the main valve, located in the water holding tank of the toilet, for a period of time that is determined by the operator. When the valve is opened slightly, downward pressure on the valve and suction forces the water passing between the valve and valve seat to exert a downward force on the valve that causes the valve to pull back into a closed position after opening. When the valve is raised to a position where its buoyancy exceeds the downward pressure a full flush is effected. The system includes the means to limit the upward lifting of the valve by limiting the lengthwise travel of a cord attached to the valve. The cord is attached on its other end to a flush handle and lever.
For background purposes and as indicative of the art to which the invention relates, reference may be made to the following remaining patents found in the search:
______________________________________ U.S. PAT. NO. INVENTOR ISSUED ______________________________________ 5,005,225 Pasquin 9 April 1991 5,004,462 Mahler 2 April 1991 5,003,644 Huang 2 April 1991 5,003,643 Chung 2 April 1991 4,969,218 Comparetti 13 November 1990 4,953,237 Perkins 4 September 1990 4,945,580 Schmitt, et al 7 August 1990 4,864,665 Toltzman 12 September 1989 4,829,605 Agostino 16 May 1989 4,817,216 Auman 4 April 1989 4,042,982 Contreras 23 August 1977 ______________________________________